Electric switch



Jan. 7, 1941. 'J'. BIE RENFELD 2,227,434 ELECTRIC SWITCH Filed Feb. 4,1958 4 sheets-she t 1 Jan. 7, 1941.

J. BI ERENFELD- 2,227,434 ELscTnIcswI'rCH Filed Feb. 4. 1958 4 Sheets-Sheet 5 4 IN VENTOR crcflf'el l J'asEf'Zz ATTORNEY Jan. 7, 1941- J.BIERENFELD 2,227,434

ELECTRIC SWITC H IN VENTOk J 5 7 ZZerarz/eid.

Patented Jan. 7, 1 941 uNn'so sTArss PATENT orrics I examine a JosefBierenfeid, Milwauk Wile assignor to Square D tionof Michigan Company,Detroit, Mich a corpora- Application February 4; 1938, Serial No.188,592 '2 Claims. (Cl. 200-144) This invention relates to electriccircuit controlling devices and more particularly to electromagneticallyoperated electric switches.

One object of the invention provides an electric 5 switch with animproved form of contact chamber providing an entrance opening in thebottom wall through which extends the manipulable means supporting themovable contact and a second top opening in the chamber, both of saidopenings providing means for venting gases from within the chamber.

Another object of the invention is to provide an electric switch with acontact enclosing chamber formed of two pieces which together cooperateto is form all the chamber walls and venting openings to the exterioroithe chamber. I

Another object of the present invention is an electric switch having animproved form of contact chamber arrangement wherein there is pronovided substantially a single opening providing for the venting of arcgases from the interior oi'ethe chamber.

' Another object of the invention is to provide in .an electric switch acontact enclosing chamber 25 formed of two pieces with the rear piecesbeinl provided with formations slidably receiving the stationarycontacts and limiting removal thereof to a forward sliding movement.

Other objects andi'eatures oi the invention will so be readilyapparentto those skilled in the art 'from the following specificationand the appended drawings -illustrating certain preferredembodiments ofthe invention in which:

Figure l is a front elevational view of an electrlc switch according tothe present invention with the front contact enclosure section brokenaway in parts.

' Figure 2 is a vertical sectional view on the line Il -l1 of Figure 1.4o Figure 3 is a horizontal sectional view on th line IIIlII ofFigure 1. s

Figure 4 is a perspective view of the front section of the contactenclosure taken from the rear and bottom faces. a 5 Figure 5 is aperspective view of a stationary contact arrangement.

Figure 6 is a vertical sectional view through a modified form of contactchamber arrangement. Figure 'l is a perspective view of a top contact 50spacing slider portion irom the contact enclosure of Figure 8.

The electric switch in the preferred einbodi 'ment of theinventionincludes a back metallic supporting plate I having mounted thereon adia-55 cent the top thereof the insulating back section 2 of the contactenclosing chambers as by means of studs 2. A further insulating sheet 4may be disposed between the back plate I and the sec- 2 tion 2. Upon theback section 2 is mounted a as complementary front section I as bymeans-of studs 8. The sections 2- and 5 cooperate to form a plurality ofchambers for the cooperating contacts, as herein illustrated three,although it is understood that one or any desired number of chambers maybe so constructed.

At the juncture of, the bottom walls of the sections 2 and 5 there areprovided openings I providing ,entrance into the contact, chambers andthrough these opennigs' I extend U-shaped elements I carrying thebridging movable con- 10 tacts O which are pressed against inturned endsII on the U-shaped elements 8 by means of compression springs I2. Aspring guide post I3 is rigidly secured with'each of the U-shapedelements I to a movable insulating supporting element I4 common to themovable contact elements. I

Rigidly secured to the supporting plate I is a bracket Ii of invertedL-shape and U-shaped in cross section. Within the U iormed by the oppo-2 site sides of the bracket is disposed a stationary core member ID of Eshape upon the central leg of which is mounted an operating coil II. Thecore I. is maintained inplace by a pin Iii rigid with the bracket IU-andengaging in aslot in the back of the core piece as shown moreparticularly in Figure 2 and at its front by a similar but removable pinI8 extending through the bracket I6 and through a similar slot andremovably maintained by spring clips 2| on the bracket. At the lower endof the bracket I5 there is pivotally mounted alink 22 also U-shaped incross section and to the link 22 is pivotally mounted a bracket 23U-shaped in cross section and also U-shaped in side elevation. The link22 and the bracket 23 are pivoted together by the pin 24 and upon thepin 24 is also pivotally supported the movable armature member 25. Aspring 2e is provided for holding the armature 25 in a desired positionwhile the coil I! is deenergized.

The bracket 23 is rigidly connected to the insulating supporting memberI4 and serves to transmit movement of the armature 25 therein so as toeifect substantially vertical reclprocatory movement oi the insulatingsupport I4 and the mov- 4 scribed herein. They are of the ordinarycurrent.

responsive type and serve upon current overload to interrupt the circuitto the energizingcoil II.

The back section 2 forming the contact chamber enclosures is providedwith recesses 2| iorming the rear portions of the contact chambers andwith top backwardly extending recesses I2 dis- 0 conductor lugs 34 orconductor ends as illustrated. Upon the front portions 35 adjacent therecesses 32 are mounted terminals 3! also receiving conductor lugs I4 orconductor terminals. The recesses 3i and 32 are connected by means ofslots 38 receiving portions of the stationary contacts and alsoproviding venting openings into the chambers as will be hereinafterdescribed.

The stationary contacts are'arranged in pairs in each recess 3| spacedlongitudinally thereof, the rear contact in each pair being designatedat 31 and the front contact at 38. These contacts are relatively massivein form'and are shown in perspective in Figure 5. They include aterminal portion 39 connectible to the terminals 30 and 33, a verticalportion 4| received within the slots 36 and a contact face 42. Therecesses and slots within the back enclosure section and the stationarycontacts are so formed that the contacts are received and guided byportions on the back section so that their movement is restricted toa'forward sliding movement for removal.

The front insulating section 5 forming the contact enclosures is shownin perspective in Figure 4 and includes recesses 43 cooperating with therecesses 3| to form the chambers and rearwardly extending projections 44partially filling the recesses 32 in the rear section 2. Theseprojections and other portions on the front section are so Y cation fromthe slots 3' through the portions of therecesses 32 immediately adjacentthe projections 44 to the exterior of the contact chambers. Thearrangement of these openings is apparent from an inspection of theupper left hand portion of Figure l and of Figures 2 and 3. Within eachof the recesses 48 and 3| in the sections 5 and 2 are disposed U-shapedmagnetic elements 45 each disposed with its legs embracing the adjacentstationary contact.

With the construction herein illustrated it is seen that the contactchambers, which may be of any desired number, are formed from twocooperating insulating sections while providing for stationary contactsdisposed in pairs within the chambers and spaced apart at right anglesto the plane of the sections, which stationary contacts are readilyaccessible for inspection and removal when the front insulation sectionfor the contact chambers is removed. The openings l at the bottom wallsof the chambers through which the supports for the movable contactsextend are seen to be relatively open so that they provide venting meansfor gases generated within the chambers. Also, the slots 36 in the topwalls of the chambers cooperate with the adjacent portions of the frontrecesses in the back section to provide top vents to the exterior of thechambers. as to provide both a top and bottom vent for each of thecontact chambers with the bottom vent further serving as entrance meansfor the parts supporting and moving the movable contact elements.

A modified form of the invention is illustrated Hence it is seen theconstruction is such in Figures 6 and '1 wherein the contact enclosinginsulating chamber is formed of three sections comprising a rear andpartial top section II, a second top section II, and a front section II.The bottom walls of the sections II and II are provided with an openingll through which extends a U-shaped contact supporting element I inwhich is disposed a bridging contact plate It, maintained forwardly byinturned ends 51 on the U-shaped element II. The bridging contact I! isbiased upwardly by means of a compression spring 58 disposed between thelegs of the U- shaped element It and further enclosed by a pair ofoppositely directed U-shaped elements II and ii slidably nesting in eachother. The U-shaped elements 55, u and ii together form a completeenclosure for the compression spring II and this enclosure is sodimensioned as to substantially enclose the opening I. in the bottomwall of the contact chamber. The top section II which is illustrated inperspective in Figure 7 is received upon the back section II and servesto space the stationary contact elements and I which are relativelyloosely engaged therewith. The contact elements I! and N are connectibleto terminals rigidly mounted upon the rear section 6| similarly to theterminals II and II in the preferred embodiment of the invention andthus serving to rigidly mount the stationary contact as well as the topsection '52. The top section 52 is provided with a vertical slot II andwith a top and side recess II which cooperate to pro vide acommunicating vent from the interior of the contact chamber to theexterior thereof. The actuating and manipulable portions of the switchof this form are identical with those previously illustrated anddescribed in the preferred form.

In this modified form of contact chamber arrangement it is seen thatwhen the front section It is removed and the stationary contacts 82 andis disconnected from their terminals that the top section I! and thestationary contacts may be readily removed as a unit for removal and/orreplacement as a whole. It is seen that this contact chamber issubstantially entirely enclosed except for the single vent formed by theslot 64 and recess I. Thus, gases generated within the contact chamberwill all be vented upwardly and outwardlyfrom the contact chambersthrough the top slot since the bottom opening is substantially closed bythe spring enclosure formed by the U-shaped elements II, B and II.

While certain preferred embodiments of the invention have beenspecifically disclosed, it is understood that the invention is notlimited thereto as many variations will be readily apparent to thoseskilled in the art and the invention is to be given its broadestpossible interpretation within the terms of the following claims.

What is claimed is;

1. In an electric circuit controlling device, a rear insulating section,a forward insulating section, said sections having cooperating recessesforming a contact chamber, a rearwardly extending recess in the frontface of said rear section and above said contact chamber forming recess,a slot in the top wall of said rear section establishing communicationbetween said recesses, a stationary contact mounted on said rear sectionand having a contacting portion disposed within said chamber formingrecess, a shank portion disposed within said slot and a terminal portionoffset from said contacting and shank portion 7g and disposed in theupper recess and adapted to be rigidly connected to a terminal elementtherein, a movable contact within said chamber, and means for movingsaid movable contact to perform the switching operation. a

2. In an electric circuit controlling device, a rear insulating section,a forward insulating sec tion, said sections having cooperating recessesforming a contact chamber, a rearwardly extending recess in the frontface of said rear section and above said contact chamber forming recess,a slot in the-top wall of said rear section establishing communicationbetween said recesses, a stationary contact mounted on said rear sectionand having a contacting portion disposed within said chamber formingrecess, a shank portion disposed within said 'slot and a terminalportion offset from said contacting and shank portion and disposed inthe upper recess and adapted to be rigidly connected to a terminalelement therein, said stationary contact and rear section formationscooperating to limit movement of the contact to a straight line forwardremoval thereof and providing for self support of said station'- arycontact in its interior position independent of its connection to theterminal element, a movable contact within said chamber, and means foreffecting movement of the movable contact to perform the switchingoperation.

3. In an electric circuit controlling device, a rear insulating section,a forward insulating section, said sections having cooperating recessesforming a contact chamber, a rearwardly extending recess in the frontface of said rear section and above said contact chamber forming recess,a slot in the top wallof' said rear section establishing communicationbetween said recesses, a stationary contact mounted on said rear sectionand having a contacting portion disposed within said chamber formingrecess, a-

vshank portion disposed within said slot and a terminalportion offsetfrom said contacting and a shank' portion and disposedin the upperrecess and adapted to be rigidly connected to a term-- 5 nal elementtherein, a backwardly extending projection on said front insulatingsection disposable in said top recess to cover the stationary contactand its connection to the terminal element, said projection cooperatingwith a side wall of said recess to effect a continuation of said slotand providing for the openingthereof said chamber forming recess, ashank portion dis-- posed within said slot and a terminal portion oifsetfrom said contacting and shank' portion and disposed in the upper recessand adapted to be rigidly connected to a terminal element therein, a.second-and oppositely oil'set contact element having its terminalportion mounted at 7 the front face of the rear element with its shankportion at least partially disposable in said slot, whereby saidstationary contacts are spaced longitudinally of the contact chamber, abridging movable contact within said chamber, and means for moving saidmovable contact to perform the switching operation. A 5. In an electriccircuit controlling device, arear insulating section,a front insulatingsec- 5 tion, and an at least partial top insulating sec- .tion, saidsections when properly assembled cooperating to form a contactchamber,stationary contacts loosely supported on' said at least partial topsection and' adapted to be rigidly con- '10 nected to and supported bysaid rear section, said at least partial top section and stationarycontacts being' removable as a unit after removal of said front section,a bridging contact element within said chamber movable into and outuof15, I

engagement with saidstatlonary contacts, means' extending into saidchamber for effecting movement of the movable contacts, and a' slotinsaid at least partial top section between said stationary-contacts andcommunicating with the 20 exterior atmosphere to, provide a vent'iorgases generated within the chamber, said slot extend: lng verticallythrough said at least partial top section and communicating with arecess in the topside wall thereof, the rear section having a 25 topportion engageable with the top or said at least partial top portion,whereby said vent, after t leaving the contact chamber, communicateswith I the exterior through an orifice disposed in a vertical plane. a 16. In an electric circuit controlling device, a plurality of insulatingsections cooperating, when properly assembled, to forma'contact'chamber, with an elongated slot in the-top wall of saidchamber leading to the interior thereof, station- 86 ary contactsmounted within said chamber spaced longitudinally thereof. and havinginte- 1 gral connection means extending'through'said slot and connectedto terminals mounted at the ment within said chamber, the bottom wallof, said chamber being providedwith an opening through which extend themeans for supporting and moving said bridging contact element, said vslot serving asa vent forgases generated by an 46 are drawn between saidcontacts and contact element, with the front and back walls of the slotformed by the integral, connecting means of the stationary contacts. i

7. In an electric circuit controlling device, a 0 rear insulatingsection, a' forward insulating lection, said sections having cooperatingformations which form a contact chamber when the sections are properlyassembled, a slot in the top wall of said rear section leading from saidoon- 65 tact chamber to the exterior therieof', a stationary contactmounted on said rear'section-and' having integral connection "meansextending through said wall and secured toa'terminal v mountedv on saidrear section at the ex- '00 terior of the chamber, said rear section andintegral connection means for the stationary contact having cooperatingformations limiting removalof said stationary contact to a straight Iline forward movement whereby to provide for 65 self-support of thestationary contact in its interior position independent ofitsconnection. to the terminal, a' movable contact within said chamber, andmeans for eifecting movement of. the movable contact to perform theswitching 1 operation. Q

exterior of the chamber, afb'ridging contact elev40'

